Objective: To study the inhibition effect of E. coli cytosine diaminase (CD)/5-flurocytosine (5-FC) system on the growth of human pancreatic carcinoma cell line cells.
Methods: Recombinant retroviral vector expressing CD genes was transduced into pancreatic carcinoma cell line cells. In vitro and in vivo prodrug sensitivity assays were carried out, including: (1) detection of growth and colony forming inhibition rate of transduced cells in the presence of 5-FC; (2) observation of bystander effect by MTT method; (3) observation of the growth inhibition effect of 5-FC on transduced cell xenografts in nude mice.
Results: The growth and colony forming inhibition rate of the transduced cells in the presence of 5-FC were 80.0% and 79.0%, which were obviously higher than 4.8% and 5.0% (P < 0.01) of nontransduced cells. Mixed cells containing only 10% of transduced cells showed 50.7% reduction of proliferation (bystander effect). The growth of transduced cells xenografts could be totally regressed by 5-FC.
Conclusions: CD/5-FC system is a potential gene therapy strategy for pancreatic carcinoma.